Field
Example embodiments relate, in general, to apparatuses and processes for naturally recycling protein waste into feed and, more specifically, to apparatuses and processes for enzymatic digestion or acidic digestion, emulsification and, optionally, drying of protein waste including feathers for use as or in animal feed.
Description of the Related Art
A mass of waste is accumulated on a regular basis in such operations as poultry production facilities. Protein waste such as carcasses from dead or recently euthanized birds from poultry production facilities pose problems for disposal. Such problems include odor and generation of bacteria in the building or anywhere such waste is left for a period of time. Carcasses are currently disposed of in many ways including land filling and burning, each of which comprise attendant problems.
Natural gas production from waste materials is also known in the art. Such processes typically also result in a byproduct which is used as animal feed or fertilizer.
Some facilities process the protein waste to produce a component for animal feed. These plants often are not designed to provide a mostly closed system. Consequently, air, moisture, and other contaminants may enter creating an environment where microorganisms can multiply and destroy the quality or usefulness of the processed protein waste.
And, although there may be processing plants from which protein waste may be acceptably disposed and recycled, there is not an efficient way to remove the waste from the site to the processing plant in such time and condition as necessary for efficient processing. The timing of such removal is essential to managing toxicity and odors; on the other hand, it is typically not feasible for each animal production plant to also operate a processing plant for its protein waste.
Animal feed requires a protein component. In addition to the carcasses which can be processed for protein recovery, feathers are inexpensive and also high in protein, however, feathers are difficult for animals to digest. And, although there are processes known for forming feather meal, often these processes require steam which, if too hot, will denature the proteins in the feathers and reduce their nutritional values. Alternatively, it is also known that certain bacterial strains produce keritinase which is an enzyme capable of degrading feathers and that, properly employed, such degradation can result in material that can be used in animal feeds. See U.S. Pat. Nos. 4,908,220; 4,959,311.
Another approach for recycling protein is known in the art and provides means to grind swine or poultry carcasses and then mix it with ingredients that will facilitate fermentation of the waste. See U.S. Pat. No. 5,713,788. The invention disclosed therein provides a specific grinding mechanism which includes a grinding drum with a helical groove on its outer surface in which a length of chainsaw chain, teeth side out, is positioned. This invention does not include a way to re-circulate and thoroughly mix the ground protein and catalyst but, instead, depends on a metered application of catalyst to the ground protein waste as it moves past the grinder wherein the metering of the catalyst is triggered by the load on the grinder. This is deficient in that no additional mixing of the ground protein and catalyst is contemplated such that there is substantial risk that it will not be appropriately mixed and the catalytic action will be hampered.
What was needed was an approach for animal production facilities to efficiently and timely dispose of animal waste in the form of carcasses in a way that is non-toxic and odor free. In addition, the approach should be affordable for the animal production facilities and the resulting recycled product must be usable. Preferably, a mostly closed system should be used to eliminate environmental contaminants and to provide avenues for recycling by-products. Finally, for any disposal of feathered animals, the system must provide a method of breaking down not only softer protein sources, but also feathers and in a manner that does not denature or destroy the food value of the proteins.
Example embodiments provide a system wherein animal carcasses such as poultry carcasses from dead or recently euthanized poultry are processed in such a way that a portion of the system may be mobile and can be taken from one animal production facility to another or simply positioned at one facility until it reaches capacity.
Example embodiments also provide a protein processing system which is capable of degrading feathers without destroying their food value.
Example embodiments also provide a way for many different and maybe distant animal production facilities to have routine access to a processing facility.
Example embodiments also provide a means for recycling and breaking down the carcasses comprising animal protein wastes and to recycle by-products of the process.
Example embodiments also provide an apparatus with mixing and grinding capabilities associated with one another in a manner that results in a mostly closed system which may be an efficient process for digesting, emulsifying and drying the recycled protein waste while also providing a means for recycling other byproducts such as water and for minimizing growth of damaging microorganisms. Example embodiments provide a process for grinding proteinaceous material with acid or to which acid is added to be used as an acidic digest, along with enzymes, generally proteases, to from an acidified digest medium. This medium is of acidic pH. The medium may be heat shocked and, optionally, emulsified. Additional proteinaceous material may be added to this medium on farm to form a stable product that may be stored for up to about 25 days. The stable product may be packaged; emulsified prior to packaging; and/or dried, with or without a carrier that may include yeast to result in a protein-containing product that may be fed to animals. Some embodiments that include grinding acidified proteinaceous material employ the aforementioned heat shock, and/or a second emulsification step, others do not.
Example embodiments provide a process that may be performed without sodium bisulfite: sodium bisulfite is known to scavenge B vitamins and B complex.
Example embodiments include the use of phosphoric acid. In that case, the acid acidifies and frees up phosphate which has benefits to animal health, particularly relative to bone health. Other acids may be employed that may not result in contribution of phosphate to the end product but still produce a useful product.
Example embodiments may also provide an apparatus for recycling animal protein that produces fuel from the digesting or fermentation of animal protein waste.
Example embodiments may also provide an apparatus for animal protein recycling that produces fuel and uses the produced fuel to power portions of the apparatus.